I came across the following paragraphs discussing the holiness of the church based on the Nicene Creed's attributes of the church: One, Holy, Catholic, and Apostolic Church. The quote is taken from The Church: One, Holy, Catholic, and Apostolic by Richard D. Phillips, Mark E. Dever, and Philip Graham Ryken.
Holiness is a prominent theme in the NT teaching about the church. What is the church? It is the holy people of God. We have ‘a holy calling’ (2 Tim. 1:9); we are ‘set apart as holy’ (2 Tim. 2:21); we were chosen to ‘be holy’ (Eph. 1:4); we are ‘God’s chosen ones, holy and beloved’ (Col. 3:12). The Bible identifies us as ‘a holy priesthood’ (1 Peter 2:5), ‘a holy nation’ (1 Peter 2:9), and a holy temple (1 Cor. 3:17; cf. Eph. 2:21). In fact, this is why Jesus died on the cross. It was ‘so that he might present the church to himself in splendor, w/o spot or wrinkle or any such thing, that she might be holy . . .’ (Eph. 5:27; cf. Col. 1:22).
The holiness of the church is the logic behind the remarkable word that the Bible uses to describe Christians: ‘saints’ – literally, ‘the holy ones.’ The New Testament repeatedly uses this word to identify believers in Jesus Christ: ‘To the saints who are in Ephesus’ (Eph. :); ‘To all the saints in Christ Jesus who are at Philippi’ (Phil. 1:1); ‘to the saints . . . in Christ at Colossae’ (Col. 1:2). ‘Saint’ is not a term the Bible reserves for a special category of Christians. Sainthood is not a lifetime achievement award – a merit badge for people who volunteer to teach junior high Sunday school, do door-to-door evangelism, and attend evening church. It is the term the Bible uses for every believer. The church is so holy that every one of its members is a saint. -47-48
GBC - The Holy Church: The Nicene-Constantinopolitan Creed
GBC - The Nicene Creed
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